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In a two-factor ANOVA with replication, if the interaction effect is statistically significant, then the relationship between one factor and the response may depend on the level of the other factor.

A hospital compares the average check-in processing time, in minutes, for patients using a new kiosk and patients using the traditional desk. Use the following data: Kiosk group: n₁ = 80, x̄₁ = 16.8, s₁ = 4.0 Desk group: n₂ = 125, x̄₂ = 18.1, s₂ = 5.0 What is the z test statistic?

A warehouse finds that 7% of shipped packages are delayed. What is the probability that the next 4 independent packages are all delayed?

A food-quality analyst compares mean freshness scores from four packaging methods. Excel one-way ANOVA output shows: F = 2.086P-value = 0.132F crit = 3.238α = 0.05 Which conclusion is correct?

A parking garage records an average of λ = 2.7 payment machine errors per week. Assume weekly errors follow a Poisson distribution. What is the probability that exactly 5 payment machine errors occur next week?

A one-way ANOVA compares mean heat-resistance scores from 5 coating formulas. The p-value is 0.009 at α = 0.05. Which interpretation is correct?

A researcher is constructing a 90% confidence interval for a population proportion. What is the positive critical value for alpha/2?

A 95% confidence interval for a population proportion is constructed from a sample with p-hat = 0.42. The value of q-hat should be calculated as 1 – 0.42 = 0.58.

A transportation analyst randomly samples 260 morning commuters and finds that 91 of them used a park-and-ride lot. For constructing a confidence interval for the population proportion of morning commuters who use park-and-ride lots, what is the value of q-hat? Round to 3 decimal places.

A bottling machine is designed to fill containers with a mean of 25.00 ounces. A technician claims the mean fill amount is different from 25.00 ounces. Use: α=0.01 n=64 x-bar=24.72 σ=1.60 Which answer gives the correct test statistic and decision?